Just a quick note to let you know that the Config files inside your sys/profile directories (on windows anyway) may not be being backed up properly as a folder by your OS System backup software.
I needed to get some old config files back for comparisons and found out that the backup software our vendor was using saw the SYS folder as a file rather than a folder and would not restore it, if you browse to it from Win7 it shows up as a shortcut. But on Server 2003 it is definitely a folder with no shortcut hints.
Now it may be that these files are buried somewhere else in SAP I have no idea about but if you are like me, not being able to restore things back where you want them to be gives you the jitts then it might just pay to make sure you can get those files back from your OS and your backup software!
(Backup software used by the vendor is HP Dataprotect so is full enterprise software).